Fig. 3: Response function for the drought recovery within a single growing season.
From: Widespread spring phenology effects on drought recovery of Northern Hemisphere ecosystems
a–f, Response function along each independent variable (x axis), including total precipitation during postdrought period (Precippost) (a), mean vapour pressure deficit during postdrought period (VPDpost) (b), mean NDVI in the 6 months preceding the extreme drought events (NDVIpre) (c), mean annual temperature (MAT, °C) (d), the start of growing season of drought year (SOSdrought_year, d) (e) and mean VPD during the drought response lag period (VPDlag) (f). The y axis in a–f shows the drought recovery (months). Shaded areas of different colours in a–f are the 95% CIs for different vegetation types. The bootstrap method was used to compute the average over all the predictions of drought recovery and the 95% CI. g, Normalized variable importance (unitless) for the drought recovery of different vegetation types. Four kinds of vegetation types were considered and compared, including evergreen forests, deciduous forests, shrubs and grasses (Methods). Precippre, total precipitation in the 6 months preceding the extreme drought events; VPDpre, mean VPD in the 6 months preceding the extreme drought events; Preciplag, total precipitation during the drought response lag period; MAP, mean annual precipitation; PrecipCV, coefficient of variation of mean annual precipitation; and TempCV, coefficient of variation of mean annual temperature. Numbers in the legend indicate the sampling sizes. The z-scores were calculated for Precippost, VPDpost, NDVIpre, VPDlag, Precippre, VPDpre and Preciplag before the RF analysis.
